1. Field of the Invention
The present invention relates to a rotary type continuous filling apparatus which continuously fills containers with a filling liquid.
2. Prior Art
Japanese Utility Model Application Publication (Kokoku) Nos. S59-42399 and S63-637, for instance, disclose a typical rotary type continuous filling apparatus. This rotary type continuous filling apparatus is equipped with: a tank installed on a continuously rotating filling rotor; a plurality of filling nozzles which are disposed in vertical positions at equal intervals around the periphery of the filling rotor; pump devices which are disposed in positions that correspond to the respective filling nozzles and in each of which a piston reciprocates upon the rotation of the filling rotor, so that a filling liquid is sucked into a cylinder from the tank and discharged toward the corresponding filling nozzles from the cylinder; and conveying means which are disposed beneath the respective filling nozzles in positions that correspond to the filling nozzles and which hold and rotationally convey containers jars). In this filling apparatus, while the filling rotor rotates once, empty containers are received by the conveying means, the containers are filled with a filling liquid while being rotationally conveyed, and then the filled containers are eventually discharged.
However, the above rotary type continuous filling apparatus has problems. The cylinders of the pump devices are installed in vertical positions. As a result, the space occupied by the cam mechanisms that cause the pistons to move upward and downward beneath each pump device tends to be large. In addition, a downward load is applied to the cam members in the upward movement of the pistons, and an upward load is applied in the downward movement of the pistons. Moreover, a load is applied from all of the pistons. Thus, the overall load is extremely large, the cam members and surrounding structure must be made strong, increasing the size of the cam mechanism and the size of the apparatus itself.
In the above apparatus, furthermore, the cylinders of the pump devices are vertical, and the discharge ports are located at the upper ends of the cylinders. As a result, when the flow passages from the tank to the cylinders and filling nozzles are cleaned, liquid may accumulate inside the upper end portions of the cylinders. Moreover, the flow passages that connect the discharge ports of the cylinders with the filling nozzles are long. And liquid tends to accumulate in these flow passages. Thus, the cleaning characteristics are poor.
The present invention solves the above problems.
The main object of the present invention is to provide a rotary type continuous filling apparatus which allows the cam mechanisms and the apparatus itself to be made compact, and which is superior in terms of cleaning characteristics.
Other objects of the present invention are, among others, to accomplish the improvement in the filling precision, to prevent accidents that involve knocking of the pistons inside the cylinders, and to prevent the contamination of the bag openings when bags are filled.
The above objects are accomplished by a unique structure for a rotary type continuous filling apparatus that includes:
a tank installed on a continuously rotating filling rotor,
a plurality of filling nozzles disposed in vertical positions at equal intervals around the periphery of the filling rotor,
pump devices disposed in positions that correspond to the respective filling nozzles, in each of the pump devices a piston making a reciprocating motion upon the rotation of the filling rotor, so that a filling liquid is sucked into a cylinder from the tank and discharged toward the corresponding filling nozzle from the cylinder, and
conveying means disposed beneath the respective filling nozzles so as to positionally correspond to the filling nozzles, the conveying means holding and rotationally conveying containers, and
in this filling apparatus, while the filling rotor makes one rotation the containers are received by the conveying means, the containers are filled with the filling liquid while being rotationally conveyed, and the containers are then discharged, and
the respective cylinders of the pump devices are installed in substantially horizontal positions with their discharge openings facing outward.
In the above structure, besides jars, the above-described containers include bags accommodated in retainers.
The above-described pump devices are equipped with cam mechanisms that reciprocate the pistons. In a desirable configuration of the cam mechanisms, the cam mechanisms have a common piston operating cam and cam rollers. The piston operating cam has an annular cam groove that surrounds the axial center of the filling rotor and is disposed so that it can move to the left and right within a horizontal plane and then appropriately positioned. The cam rollers are connected to the pistons and move along the cam groove. Thus, the pistons make a reciprocating motion as a result of the cam rollers moving along the cam groove as the filling rotor rotates. The cam rollers are connected to the pistons via swing levers which are connected to the rear ends of the pistons so that the levers are horizontally rotatable, vertical supporting shafts which are fastened to the swing levers and attached to the filling rotor so that the shafts are rotatable, and cam levers which are fastened to the supporting shafts.
Furthermore, desirably, each of the filling nozzles comprises a nozzle main body and an up-and-down piston. The nozzle main body has a supply opening, which communicates with the tank in the sidewall of the nozzle main body, a feed-out opening which communicates with the cylinder below the supply opening, and a discharge port at the lower end of the nozzle main body. The up-and-down piston has a flow path switching valve that switches between communication and non-communication of the supply opening and feed-out opening, and a discharge port opening-and-closing valve at the tip end. When the up-and-down piston is raised inside the nozzle main body, the supply opening and feed-out opening are brought in a non-communicating state, and the discharge port is opened. When the up-and-down piston descends inside the nozzle main body, the supply opening and feed-out opening are brought in a communicating state, and the discharge port is closed.
The above filling nozzles are used in a rotary type continuous filling apparatus which has cylinders that are disposed in substantially horizontal positions with the discharge openings that face outward. The above filling nozzles are also used in rotary type continuous filling apparatuses in general which have cylinders disposed in other configurations, e.g., cylinders that are disposed in vertical positions, etc.
In cases where the rotary type continuous filling apparatus fills bags, which are accommodated in retainers, with a filling liquid, it is preferable to design so that the conveying means rotationally convey the bags together with the retainers, a means that raises and lowers the bags together with the retainers while the bags and retainers are being rotationally conveyed is installed, and the opening and closing of the discharge port of each filling nozzle is controlled by an electromagnetic valve. Needless to say, the timing is set so that the raising movement of the retainer with bags therein is performed prior to the discharge of the filling liquid by the filling nozzles and the lowering movement is performed after this discharge. Furthermore, the bags and retainers are raised to a height where the tip ends of the filling nozzles are inserted into the bags.
With the conveying means and filling nozzles having the above configuration, the conveying means and filling nozzles can be used not only in a rotary type continuous filling apparatus which has cylinders that are disposed in substantially horizontal positions with the discharge openings facing outward, but also in rotary type continuous filling apparatuses in general which have cylinders disposed in other configurations, e.g., cylinders that are disposed in vertical positions, etc.